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arXiv · 0809.1116

Anomalous circular polarization of magneto-photoluminescence from individual CdSe nanocrystals

H. Htoon·S. A. Crooker·M. Furis·S. Jeong·Al. L. Efros·V. I. Klimov
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Abstract

We study the low-temperature magneto-photoluminescence (PL) from individual CdSe nanocrystals. Nanocrystals having a small "bright" exciton fine structure splitting ($<$0.5 meV) exhibit a conventional left- and right-circularly polarized Zeeman PL doublet in applied magnetic fields. In contrast, nanocrystals with large fine structure splitting ($>$1 meV) show an anomalous magneto-PL polarization, wherein the lower-energy peak becomes circularly polarized with increasing field, while the higher-energy peak remains linearly polarized. This unusual behavior arises from strong mixing between the absorbing and emitting bright exciton levels due to strong anisotropic exchange interactions.

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H. Htoon, S. A. Crooker, M. Furis, S. Jeong, Al. L. Efros, V. I. Klimov. 2008-09-05. Anomalous circular polarization of magneto-photoluminescence from individual CdSe nanocrystals. https://doi.org/10.1103/physrevlett.102.017402

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